python package building failure over C++ absl api version

[matanox]

OS Platform and Distribution

Ubuntu 24.04

Compiler version

gcc (Ubuntu 13.3.0-6ubuntu2~24.04) 13.3.0

Programming Language and version

python 3.12

MediaPipe version

latest + #6131

Bazel version

7.4.1

Problem Description

Multiple issues arise when following docs/getting_started/python.md for building the python package from source:

1. seems that setuptools should be installed but missing from requirements.txt (or at least it fails when it is not installed).
2. the __version__ variable in setup.py must be modified in order to be PEP 440 compliant, otherwise the script raise.

These are just annoyances, probably the build doesn't assume python 3.12 or the python package dependencies which pip brings in for 3.12, or, the stricter pip that comes with 3.12.

But then the build currently fails over a mediapipe C++ core issue:

$ python3 setup.py install --link-opencv
ERROR: /home/user/code/mediapipe-current/mediapipe/python/pybind/BUILD:27:15: Compiling mediapipe/python/pybind/calculator_graph.cc failed: (Exit 1): gcc failed: error executing CppCompile command (from target //mediapipe/python/pybind:calculator_graph) /usr/bin/gcc -U_FORTIFY_SOURCE -fstack-protector -Wall -Wunused-but-set-parameter -Wno-free-nonheap-object -fno-omit-frame-pointer -g0 -O2 '-D_FORTIFY_SOURCE=1' -DNDEBUG -ffunction-sections ... (remaining 126 arguments skipped)

Use --sandbox_debug to see verbose messages from the sandbox and retain the sandbox build root for debugging
mediapipe/python/pybind/calculator_graph.cc: In lambda function:
mediapipe/python/pybind/calculator_graph.cc:441:50: error: no matching function for call to 'absl::MutexLock::MutexLock(absl::Mutex&)'
  441 |               absl::MutexLock lock(callback_mutex);
      |                                                  ^
In file included from external/com_google_absl/absl/strings/internal/cordz_info.h:31,
                 from external/com_google_absl/absl/strings/cord.h:90,
                 from external/com_google_absl/absl/status/internal/status_internal.h:26,
                 from external/com_google_absl/absl/status/status.h:65,
                 from mediapipe/python/pybind/calculator_graph.cc:22:
external/com_google_absl/absl/synchronization/mutex.h:588:12: note: candidate: 'absl::MutexLock::MutexLock(absl::Mutex*, const absl::Condition&)'
  588 |   explicit MutexLock(Mutex* mu, const Condition& cond)
      |            ^~~~~~~~~
external/com_google_absl/absl/synchronization/mutex.h:588:12: note:   candidate expects 2 arguments, 1 provided
external/com_google_absl/absl/synchronization/mutex.h:581:12: note: candidate: 'absl::MutexLock::MutexLock(absl::Mutex*)'
  581 |   explicit MutexLock(Mutex* mu) ABSL_EXCLUSIVE_LOCK_FUNCTION(mu) : mu_(mu) {
      |            ^~~~~~~~~
external/com_google_absl/absl/synchronization/mutex.h:581:29: note:   no known conversion for argument 1 from 'absl::Mutex' to 'absl::Mutex*'
  581 |   explicit MutexLock(Mutex* mu) ABSL_EXCLUSIVE_LOCK_FUNCTION(mu) : mu_(mu) {
      |                      ~~~~~~~^~
INFO: Found 1 target...
Target //mediapipe/python:_framework_bindings.so failed to build
Use --verbose_failures to see the command lines of failed build steps.
INFO: Elapsed time: 169.311s, Critical Path: 67.72s
INFO: 3137 processes: 369 internal, 2768 linux-sandbox.
ERROR: Build did NOT complete successfully

[matanox]

Also noting in passing, that bazel building the python //mediapipe/python/... targets in isolation from pip, raises other errors , where the purpose of bazel building it there is to confirm the building of many bazel targets in isolation from pip, which perhaps is not supported for specifically the python bazel targets.

[matanox]

The above error solves thanks to and inspired by @HarishPermal's #6131 by updating of the use of absl::MutexLock. Which suggests, that my build is pulling in a newer absl version than assumed by the latest source code of mediapipe. Which shouldn't happen actually.

[matanox]

the WORKSPACE file is supposed to bring in a specific and patched version:

# ABSL on 2023-10-18
http_archive(
    name = "com_google_absl",
    patch_args = [
        "-p1",
    ],
    patches = [
        "@//third_party:com_google_absl_windows_patch.diff",
    ],
    sha256 = "f841f78243f179326f2a80b719f2887c38fe226d288ecdc46e2aa091e6aa43bc",
    strip_prefix = "abseil-cpp-9687a8ea750bfcddf790372093245a1d041b21a3",
    urls = ["https://github.com/abseil/abseil-cpp/archive//9687a8ea750bfcddf790372093245a1d041b21a3.tar.gz"],
)